Electrodeposition of nickel

ABSTRACT

It has been found that certain unsaturated aliphatic sulfonic acids characterized by having four aliphatic carbon atoms and two separate aliphatic unsaturated linkages, such as the allene sulfonic acid CH2 C C-CH2SO3H are excellent when used in acidic nickel plating baths in making it possible to obtain lustrous ductile nickel plate over a very wide plating range. These sulfonic acids do not have critical upper concentration limits.

United States Patent Fuchs et al,

ELECTRODEPOSITMUN 0F NICKEL Charles F. Fuchs, Evanston, 111.; lllenryBrown, Huntington Woods, Mich.

lnventors:

[1.5. CI ..204/49 lint. Cl. .1 C231) 5/08, C23b 5/46 Field of Search..204/49, 44, 43, l 12;

References Cited UNITED STATES PATENTS Brown ..204/49 1 Feb, l, M72

2,800,440 7/ l 957 Brown ..204/49 2,841,602 7/1958 Brown et a ...204/49X 3,306,83l 2/1967 Cope ..204/43 3,428,536 2/ 1969 Towle et a1 .104/49Primary Examiner-G. L. Kaplan AttorneyStanley H. Lieberstein and WilliamJ. Schramm [5 7] ABSTRACT It has been found that certain unsaturatedaliphatic sulfonic,

16 Claims, N0 Drawings ELECTRODEPOSITION OF NICKEL TABLE IConcentration, g./l.

1 CH2==C=CHCH:SO:H 0.1-10 2 CHz=CH-CH=CHSO;H 0.1-10

3 -CH=C=CHCHz-SO3H 0. -8

4 CHa=C=(IJ-CH S 01H 0.05-8

5 CH:=(]3CH=CHS 03H 0.05 8

f 6 CH2=CH--(|J=CHS 03H 0. 05-8 1 CHz=C=CH-C|1H-S 03H 0.05-8

s CHz=CH-CH=(]J-S 03H 0. 05-8 9 -oH=oH-oH=oH--s 03H 0. 058

10 |3H=OHS03H 0.05-s

11 t m=ons 0,11 0. 05-8 OH=CHS 0,11.

12 0H=0Hs05rt 0.05-8

[1]., IICEC-CH=CH-S 03H 0. 0H

14 HCEC(|J=CI[S 03H 0.05-8

TABLE I] Cone. all.

1. o-henzoyl sulfimide 005-4 2. benzene sulfonamide 0.1-3

3. toluene sulfonamides 0. l-Z

4. enzene monoand disulfonic acids (Lil-l5 5. naphthalene cliandtri-sulfonic acids (LL-t (a. o-sulfobenzaldchydc 0,33

8. his-toluene suliunimitles 0, I4

It has now been found that the unsaturated aliphatic sulfonic acidsshownin table I are unusually effective in decreasing the grain size andincreasing the luster and brightness of nickel deposited from aqueousacidic: nickel-plating baths, without seriously decreasing the ductilityof the plate or the current density range of the nickel bath. Thecompounds of table I are more effective than the aliphatic (four) carbonatom compound: 2-butyne-l,4-disulfonic acid in that they producebrightness and luster with much lower concentrations of material, andare vastly superior to the aliphatic (four) carbon atom compound:2-butene-l,4-disulfonic acid in producing brightness and luster at anyconcentration. The compounds of table I are also far superior toZ-butene-l-sulfonic acid in producing luster without seriouslydecreasing the ductility of the plate or causing tensile stresses. Theunsaturated aliphatic sulfonic acids of this invention cooperate to givenickel plate of high brilliance and leveling when used in conjunctionwith unsaturated compounds, such as those carrying thev C= N unsaturatedlinkage, for example, pyridine, quinoline, isoquinoline and their saltsand especially their quaternary salts, or the unsaturated C C linkage asin coumarin, or the unsaturated C :;C linkage as in dimethylethynylcarbinol or butyne-diol, or the unsaturated allene linkage as in CHC=CHCHZOH, CH =C= CHCH OC H OH, and CH C=CHCH OCH CHOHCH CL or theunsaturated C N linkage as in ethylene cyanohydrin. or the unsaturatedC=O linkage as in bromal, or of combinations of these types ofunsaturated compounds. When one or more of the compounds of table I areused. with the above types of unsaturated compoundsand with one or moreof the wellknown benzene and naphthalene sulfonic acids, sulfonarnidesand sulfonimides illustrated in table ll, maximum ductility is obtainedfor the brilliant high levelling nickel K late. mm

p The iirTs'iifrhtd aliphatic sulfonic acids illustrated in table I areeffective not only in the Watts high nickel sulfate concentration baths,but also in high chloride, sulfamate or fluoborate nickel baths ormixtures of these baths and salts. The concentrations of table lcompounds in the nickel baths are not critical, though in general, nofurther improvements in luster or ductility are obtained withconcentrations above about 10 grams per liter. The bathsoluble salts ofthe sulfonic acids of this invention are preferred for easier handlingespecially the sodium or potassium salts. In the acidic nickel baths,the compounds of table I are, of course, present mainly as thesulfonicacids and their nickel salts even if added to the baths assodium or potassium salts or for that matter. cobalt, magnesium or othersalts.

The compounds of table 1 may have halogen atoms substituted for some ofthe hydrogen atoms, with at the most two halogen atoms per molecule. Thehalogen atoms may be on the benzene rings as well as on the aliphaticportion of the molecules. in compound I of table I, for example, achlorine or bromine atom could replace one or both of the hydrogen atomson the carbon next to the sulfonic group with improved results in lusterof the nickel plate. Also one or two fluorine, chlorine, bromine oriodine atoms can be present, for example, on the benzene ring ofcompound of table I with slightly improved results in luster of thenickel deposit. In most cases,

' the improvements are only slight from the presence of halogen atoms inthe compounds of table l. The best pH range for the acidicnickel-plating baths employing the compounds of table I is from about2.5 to 5.5. The bath temperatures may be from room temperature to atleast 180 F., and in this respect, the brighteners of table I used bythemselves or with unsaturated compounds, such as a quaternary ofpyridine or quinoline, or in conjunction with butynediol or a monoordi-ethylene oxide adduct of butynediol are superior to the well-knownbrighteners of table ll used alone or with the unsaturated compounds.The compound of table [I may be used in amounts of from 0.l g./l. tosaturation.

Below are listed some preferred examples of baths for the production ofbrilliant nickel plate, with bright plate range from the highest currentdensities down to the very lowest current densities.

EXAMPLE I Grams per Liter ZOO-300 NiCI.,'6H,O 30-60 H BO, 40 Compound 2of table I l-4 Allyl quinaldinium hromidc 0.003-(L0l Compound I of tableII Compound 8 of table ll 7 The plate from nickel baths with one or moreof the compounds of table I present are remarkably free from pittingespecially when the concentration of the compounds is about 0.5 g./l.and higher. In general, however, a surface-active agent such as sodiumn-octyl sulfate or sodium 2-ethyl hexyl sulfate in concentrations of 0.1to l g./l. is preferred to be used in air'agitated baths, and sodiumlauryl sulfate or sodium lauryl ethoxy sulfatewith non-air-agitatedbaths. The plate of highest brilliance as previously mentioned isobtained by the conjunctive use of unsaturated class II nickelbrighteners as EXAMPLE II Grams per liter NlCh-BH 0.; 100-220 NlSO -6H0. o-so H BO; 40 Compound 1 01 Table I 2-4 Compound 1 of Table 11.. 1-6Compound 2 of Table II 1-2 (|)H HOH,C-C C-.OH,OCH CH-CH,SO3N9. 0.10.6

EXAMPLE m NiSOrH o 150400 NiCl,-6H 0 30-150 H3803 4O 0.5-3 Compound 5 oftable I shown in examples I and ll.

The table l unsaturated aliphatic sulfonic acids of this invention canbe used in very high concentrations in the acidic nickel-plating baths,in fact, up to saturation concentrations. which for some of thecompounds, for example, compounds I and 2, are over 100 grams/liter.However, no further improvement of luster is obtained in concentrationsabove about 10 grams/liter, but since the compounds are noncritical inconcentration, any concentration up to saturation concentrations can beused, preferably 0.05 to about 100 g./l.

The compounds of table l are just as effective as brighteners innickel-cobalt, nickel-iron and nickel-cobalt-iron alloy plating baths.The cobalt may be as high as at least 50 percent in the plate and theiron as high as at least 40 percent, and the total of cobalt plus ironmay be as high as 50 percent of the plate. With cobalt concentrations inthe plate higher than about 50 percent, it is preferred to have compoundI of table II also present in the baths. Thus, with the nickel baths andnickel plate described in this invention as in examples 1, ll and Ill,cobalt and iron may also be present in the plate to the extent of about50 percent of the plate as combined material, or as about 50 percent ofeither cobalt or iron separately, and still obtain bright plate thatbehaves essentially like bright nickel plate. It is therefore to beunderstood that the claimed nickel baths cover these nickel alloyplates.

Compounds of table I produce lustrous nickel plate even when the bathtemperatures are as high as 180 to l F.

What is claimed is:

l. A bath for the electrodeposition of fine-grained lustrous nickelcomprising essentially an aqueous acidic nickel-plating bath containingdissolved therein at least one of the unsaturated sulfonic acids listedin table I in a concentration of about 0.05 to about I00 grains/liter.

2. A bath as claimed in claim I wherein there is also present dissolvedin said bath at least one of the compounds listed in table ll in aconcentration of about 0.l gram/liter to saturation.

3. A bath as claimed in claim 2 wherein the unsaturated sulfonic acid iscompound 2 oftable l.

4. A bath as claimed in claim 2 wherein the unsaturated sulfonic acid iscompound I of table l.

5. A bath as claimed in claim 2 wherein the unsaturated sulfonic acid iscompound 5 of table l.

6. A bath as claimed in claim 1 wherein the unsaturated sulfonic acid iscompound 2 of table I.

7. A bath as claimed in claim 1 wherein the unsaturated sulfonic acid iscompound 1 of table I.

8. A bath as claimed-in claim 1 wherein the unsaturated sulfonic acid iscompound 5 of table I.

9. -A method for electrodepositing fine-grained lustrous .nickelcomprising the step of electrodepositing fine-grained lustrous nickelfrom an aqueous acidic nickel-plating bath containing dissolved thereinat least one of the unsaturated sulfonic acids listed in table I in aconcentration of about 0.05 to about grams/liter.

10. A method as claimed in claim 9 wherein there is also presentdissolved in said bath at least one of the compounds listed in table llin a concentration of about 0.1 gram/liter to saturation.

11. A method as claimed in claim 10 wherein the unsaturated sulfonicacid is compound 2 of table I. 7

12. A method as claimed in claim 10 wherein the'unsaturated sulfonicacid is compound l of table l.

13. A method as claimed in claim 10 wherein the unsaturated sulfonicacid is compound 5 of table I.

14. A method as claimed in claim 9 wherein the unsaturated sulfonic acidis compound 2 of table I.

15. A method as claimed in claim 9 wherein the unsaturated sulfonic acidis compound 1 of table l.

16. A method as claimed in claim 9 wherein the unsaturated sulfonic acidis compound 5 of table I.

2. A bath as claimed in claim 1 wherein there is also present dissolvedin said bath at least one of the compounds listed in table II in aconcentration of about 0.1 gram/liter to saturation.
 3. A bath asclaimed in claim 2 wherein the unsaturated sulfonic acid is compound 2of table I.
 4. A bath as claimed in claim 2 wherein the unsaturatedsulfonic acid is compound 1 of table I.
 5. A bath as claimed in claim 2wherein the unsaturated sulfonic acid is compound 5 of table I.
 6. Abath as claimed in claim 1 wherein the unsaturated sulfonic acid iscompound 2 of table I.
 7. A bath as claimed in claim 1 wherein theunsaturated sulfonic acid is compound 1 of table I.
 8. A bath as claimedin claim 1 wherein the unsaturated sulfonic acid is compound 5 of tableI.
 9. A method for electrodepositing fine-grained lustrous nickelcomprising the step of electrodepositing fine-grained lustrous nickelfrom an aqueous acidic nickel-plating bath containing dissolved thereinat least one of the unsaturated sulfonic acids listed in table I in aconcentration of about 0.05 to about 100 grams/liter.
 10. A method asclaimed in claim 9 wherein there is also present dissolved in said bathat least one of the compounds listed in table II in a concentration ofabout 0.1 gram/liter to saturation.
 11. A method as claimed in claim 10wherein the unsaturated sulfonic acid is compound 2 of table I.
 12. Amethod as claimed in claim 10 wherein the unsaturated sulfonic acid iscompound 1 of table I.
 13. A method as claimed in claim 10 wherein theunsaturated sulfonic acid is compound 5 of table I.
 14. A method asclaimed in claim 9 wherein the unsaturated sulfonic acid is compound 2of table I.
 15. A method as claimed in claim 9 wherein the unsaturatedsulfonic acid is compound 1 of table I.
 16. A method as claimed in claim9 wherein the unsaturated sulfonic acid is compound 5 of table I.